Modeling and experimental study of carbon dioxide absorption in a flat sheet membrane contactor

In the present study, CO₂ removal from natural gas stream has been studied using a flat sheet membrane contactor. A three dimensional mathematical model is developed to describe the process. The model considers the transport of a gas mixture containing carbon dioxide and methane through a flat sheet membrane contactor module. The model is based on the non-wetted mode of operation, in which the gas fills the membrane pores in a countercurrent gas-liquid contact. Simulation was performed using computational fluid dynamics (CFD) of the model material and momentum transport equations in the flat sheet membrane for laminar flow conditions. Physical and chemical absorptions were considered in the simulations for the absorption of CO₂ in aqueous sodium hydroxide solution. Simulation predictions were in good agreement with the experimental data for different values of gas flow rates. The modeling predictions indicate that the removal of CO₂ increased with increasing inlet liquid flow rate and increasing solvent temperature, by contrast, increase in inlet gas flow rate has negative effect.